Deerfly remedies help keep pesky NH insects from biting

It may not be fashionable, but a blue plastic cup covered with Tanglefoot and attached to a ball cap can attract and trap deerflies. (NANCY BEAN FOSTER PHOTO)

DURHAM — Circling around your head like fighter jets buzzing an enemy warship, deerflies drive folks buggy in New Hampshire during the summer, and while there's really no way to prevent them from swarming and biting, there are some things you can do to exact revenge against the annoying creatures.

Dr. Alan Eaton, of the University of New Hampshire Cooperative Extension in Durham, said that deerflies, and their larger kin, the horsefly, are drawn to human beings and other mammals by movement and the emission of carbon dioxide. On hot, humid days, sportsmen, gardeners, runners and other folks who work or recreate outside become targets for the V-winged deerflies.

There are many varieties of deerfly in New Hampshire, said Eaton, and the females feed on blood in order to help them procreate. But unlike the mosquito, deerflies aren't kept away by DEET or other chemical insect repellents.

Aside from staying indoors, people can avoid bites from the flies by covering up and wearing long sleeves and pants, denying the bugs a place to eat. But on sweltering days it can be a toss-up as to whether melting or getting eaten is worse.

But while there aren't any sprays or other deterrents on the market, there are some ways of capturing, killing, or simply exacting revenge on the dreaded deerfly.

Twenty years ago, Dale Stieg, a Christmas tree farmer in Michigan, said the deerflies became too much for him to bear while out tending his trees so he started observing their behavior and thinking of a way to get back at them. He invented a double-stick deerfly patch that adheres to the back of a baseball cap.

"The patch looks like a good landing place," said Stieg, "so the flies stop there and get themselves stuck."

After a day outdoors, the patch, and its collection of dead flies, can be peeled off and discarded.

"It sounds pretty gross to have to peel dead flies off your hat after a day of canoeing or fishing," said Leigh Duquet, owner of The Dirty Worm Greenhouse in New Hampton that sells Stieg's patches. "But they do work."

The Tred-Not Deerfly Patches are sold throughout New Hampshire at hardware stores and retailers that sell outdoor gear and equipment, or online at www.deerflypatches.com.

For those who aren't slaves to fashion, there's a home-made deerfly trap that works on the same principle as the patches, but includes a ball cap, a blue plastic cup, a pair of safety pins or paper clips and a tub of sticky stuff called Tanglefoot.

The cup is pinned to the top of the cap, smeared with Tanglefoot, which is used to keep crawling insects out of trees, and worn while outside. The humans draw the flies, but the flies like to shoot for the highest point so the cup becomes the target. Once the flies land, they're stuck. It's a great alternative to buying the patches if you don't mind the strange looks from passing neighbors.

If you've got a free hand while working or exercising outdoors, there are a number of handheld "zappers" on the market. Powered by batteries and shaped like small tennis rackets, the zappers aren't as effective at defeating a swarm of flies as the sticky alternatives, but there is something gruesomely rewarding about catching a deerfly in the electrified strands of wire of the racket and hearing it sizzle.